In 257 RAM SEEG adults aged 18–64 years, the 4–13 Hz peak-frequency spread decreased weakly with age but not after adjustment for median peak frequency and height

Among 257 adults aged 18–64 years with epilepsy, the interquartile range (IQR) of 4–13 Hz spectral peak frequencies across accepted bipolar SEEG pairs decreased weakly with age (partial Spearman rho = −0.131, 95% CI −0.254 to +0.001; permutation p = 0.036; slope −0.20 Hz per decade). The bootstrap interval touched zero. Adjustment for median peak frequency and height removed the association (rho = −0.009; Holm-adjusted p = 0.90); the IQR within 7–13 Hz did not change with age. Adjustment for median implant location and spatial spread did not remove the primary association, but the Holm-adjusted p was 0.12. These results are consistent with older patients having taller, more uniform alpha-range peaks that replace a mixture of theta and alpha peaks; they do not establish a separate age-related trait in spatial frequency spread. The analysis used one 60-second memory-task segment per patient, one peak method, and at least 10 peaked pairs per patient. Seizure-onset pairs were not removed, and implant coverage differed between patients.

SEEG · spectral peaks · peak-frequency spread · age · intracranial EEG · memory task · partial Spearman correlation